The 23-year-old failed to make the grade at Barcelona, playing just four times for the senior team between 2014 and 2021, while a loan spell at Schalke in the 2019-20 season also saw him feature in just 12 matches.
Miranda was loaned out to Betis for the 2020-21 campaign, where he immediately established himself as a regular in the Verdiblancos XI, and Barca allowed him to join Manuel Pellegrini's side on a free transfer that same summer.
Since swapping Barcelona for Betis, the left-back has come up with six goals and nine assists in 85 matches for the Verdiblancos in all tournaments and making a memorable contribution to their 2021-22 Copa del Rey triumph.
Miranda started on the bench against Valencia in the final, but he was brought on for Alex Moreno in extra time and scored the cup-winning penalty in the shootout, clinching Betis' first major honour in 17 years.
Following Moreno's move to Aston Villa, Miranda nailed down the left-back spot in Pellegrini's side and registered three goals and five assists in 31 matches last season, helping his side reach the Europa League knockout stages.
Since the start of the new term, the former Barca academy graduate has already started four La Liga games for Betis, and he scored twice during Spain's run to the final of the Under-21 European Championships, where they lost to England.
However, Miranda's contract with Betis only runs until the end of the campaign, and according to Sky Italia, Milan are hopeful of signing the left-back on a free transfer at the end of the season.
A January switch is not entirely out of the question, but Milan are supposedly not willing to pay the €6m (£5.2m) asking price which Betis and Miranda's agents are demanding.
Miranda would arrive at San Siro to play second fiddle to Theo Hernandez, who has built up a reputation as one of Europe's finest left-backs since leaving Real Madrid in 2019, but he lacks genuine cover in Milan.
Malick Thiaw is capable of playing as a full-back, but the former Schalke 04 youngster is thought to be on the radar of Real Madrid after making a name for himself under Stefano Pioli.
Blancos boss Carlo Ancelotti is expected to cope without Eder Militao for the entire campaign due to his ACL injury, while David Alaba has also struggled for fitness in the new term.
However, the report adds that West Ham United are seen as more likely to make an official bid for the Germany international, who joined for a mere €8.6m (£7.5m) in 2022.
Milan sit top of the Serie A table with 21 points from eight matches and return to action with a San Siro showdown against fellow heavyweights Juventus on October 22.